A small comparison between Facebook, Google Plus and Academia.edu has shown, that none of them is a valuable Social network. The quality in Facebook is too low (it consists mostly of funny clips), Google Plus is more serious but there is no traffic. Academia.edu is a well known Academic social network, but most papers are not from nature-science. So the remaining candidate is Researchgate. They are focussed on computer science and medicine, they have a huge amount of traffic and they have discussions with the option to upvote a researcher. The only problem with Researchgate is, that not everybody can be a member.
I have tested out the startpage. They have a button for “create account”, but then it is a bit difficult. If the user selects “I’m not a researcher” than he can’t create an account. If the user selects “I’m a researcher” in the hope that he pretends so, than researchgate wants to know the exact e-mail address of the company somebody is working. So the intention is to only let real researcher in the network and hold all trolls and fake-scientists out.
What does that mean? It results into the same filter like on Arxiv.org. If somebody has an e-mail address in a university or in a research company, he has no problem for getting an account. And most of them have such an account. It is hard to find a well known author how have written important papers about robotics, who is not member of researchgate.
So what are the options? The first alternative to Researchgate is Academia.edu which is open for everybody. It is possible to login with a normal Google account, and as far i can see, normal people have done so in the past. The second option is to use the remote comment function of a weblog to became part of researchgate without being an official member. Reading in the discussions is possible. So the url to an thread can be copy & pasted in the own WordPress blog and the answer is posted there.
I know, both alternatives are not very pleasant. But it is better than nothing. The discussion board of Researchgate starts with “https://www.researchgate.net/post/” so a simple Google search filter is all the needed information. According to the following thread https://www.researchgate.net/post/How_to_create_own_profile_and_account_in_Research_Gate_for_my_co-author_Roshchina_VD it is possible to send an invitation to a person. And here https://www.researchgate.net/post/How_many_of_you_have_an_account_on_Researchgate_and_Academiaedu_in_the_same_time is a discussion about the pros and cons of Researchgate vs. Academia.edu
Like i mentioned above the main difference is, that Researchgate has discussions, and has more traffic. And here https://www.researchgate.net/post/Are_there_fake_identities_at_ResearchGate is a discussion about fake-profiles and how to spot them. As far as i can see, the real Researchgate members have the possibility to flag a fake-profile and ban it from the network. Another option is to use ORCID for check the credentials.
The reason why Researchgate is so focussed on real names and real scientists has to do with a lack of a public peer-review system. That means, apart from Openwetware, there is no public wiki which has the aim to verify done research, so asking for the authors name is the only option the community has today. The idea is perhaps, that if only people who have a degree in science are allowed to publish in science, this will prevent spam.
And i would agree to this hypothesis. Without a peer-review wiki it is not possible to spot Fake-papers. To open up Researchgate for everyone, first a peer-review wiki has to be build from scratch. But, currently they are no projects which aim to do so.
A bit desinformation is also given in the Researchgate forum. Here https://www.researchgate.net/post/Is_it_essential_to_have_an_institutional_email_id_to_join_research_gate some guy has the opinion, that it is possible to register on Researchgate with a normal Gmail adress. But, If we are looking in the profile of the guy who has said so, he is:
• working at a university
• has a degree in PhD, B.Sc, M.Phil
• and has a long publishing list
In contrast, I have found no example, that somebody outside of the university sector has an researchgate account. On Academia.edu it is possible, on Researchgate not.